1. Field of the Invention
This invention provides means for cleaner, more efficient and rational combustion when burning wood, bio-mass or oil-shale by hand firing. It is not suitable for burning coal.
2. Description of the Prior Art
Because almost any arrangement will permit a fire to burn this is a crowded field where stoves are legion. Prior art is replete with examples where whim and witchcraft have created inadequate designs.
The generalizations which follow are intended to illumine problems which have not been identified nor adequately attacked.
Conventional stoves work at cross-purposes. Extracting heat from a firebox hinders the combustion process. When the walls of a firebox are not hot, flames and gases wiping them are quenched and the propagation of combustion stops. Catalytic burners, and their shortcomings are well known; their usage is indicative of a lack of inquiry as to why gases are unburned.
Conventional stoves neglect the powerful potential in the use of radiant heat. Air and gases are transparent to the radiant heat of fire and firebox walls and to assume that combustion air will be heated by squirting it into the fire is faulty. Air will then only be heated by diluting it with gases and the gases only cooled by diluting them with air.
Conventional stoves admit air to the firebox as a coherent stream or streams and hope that turbulence will mix the air with hot gases. At low fires, for example, there is no turbulence and mixing is particularly inadequate. To the degree that air does not contact the fuel and mix well with the gases, it fails to take part in combustion. It goes thru the firebox and up the stack for a ride. It is parasitic.
Conventional stoves make no use of the fact that surfaces with good emissivity (black) when heated by radiant heat, will act as does a mirror with light, to reradiate that heat. As with light, we can focus that heat. Shaping surfaces with the deliberate objective of focusing that radiant heat on fuel seems to be ignored.
Conventional stoves, using manual firing, have a cyclic change in the burning rate unless adjustments are somehow made. It is impractical to chain a little devil to the stove to read CO.sub.2 and adjust secondary air supplies. Likewise impractical, is an oxygen analyzer/controller--too costly. Insufficient air wastes unburned gases and smokes; too much is parasitic.
Conventional stoves have not borrowed from the old technique of making infrared or radiant heat burners which admit gas thru many ceramic ports and burn in tiny flamelets on the surface of the ceramic. This needs only to be reversed by bringing air thru a bed and bringing gases to the face.
This is indicative of the problems in Prior Art which this invention deals with.